Hadlow Down, East Sussex
Construction Time: 18 months
Completion date: July 2012
Gross floor area: 258m2
Contract value: £898K of which £125K was pool installations
Build Rate: £3,250/m2 or £2,996/m2 for building less pool
‘U’ Values: Floor 0.17 Wm2/k, Walls 0.12 Wm2/k, Roof 0.10 Wm2/k
Main Contractor: R Durtnell & Sons Ltd.
In 2008 BBM were commissioned by a private client to design a scheme for a new contemporary country house set in the stunning Sussex Weald. The project also involved the restoration of a poorly converted Listed Oast House and the design of a new pool house as well as a landscape appraisal and contemporary landscape scheme designed by Studio Engleback. The landscape design included a new outdoor ‘natural’ swimming pool with a reed bed. The project was of further interest as the client shared BBM’s commitment to low carbon development. With an estate of 275 acres, including 150 acres of standing woodland the project is well able to become self-sufficient from the point of view of energy. With this in mind BBM designed an independent energy centre for the site that creates energy from biomass sourced from our client’s estate and stores energy captured from the sun’s energy.
The master plan for the site allowed for the development works to be undertaken in two phases, the first of which delivered the heated swimming pool with its hot & cold pools plus sauna & steam room in tandem with the restoration of the Listed Oast House, the natural pool and Energy Centre. The Pool House replaced a derelict dairy building dating from the 1940’s. One of the Planning constraints imposed on the scheme was that the new pool house should match the form and volume of this building; hence the agricultural feel of this very high spec building.
The pool house is constructed with the most environmentally materials where possible, such as a timber framed structure, insulation made from waste timber fibre, and locally sourced sweet chestnut cladding. Chestnut cladding is used for the swimming pool’s beautiful curved ceiling. The internal walls are hand finished in a breathable plaster called ‘tadelakt’ – a technique from Morocco. This material was specified as it has been used for centuries in turkish bath’s and is very well suited to the particular conditions a heated pool creates. It is self-finished requiring no decorating, while providing a particularly sensuous depth and tactile feel to the pool house interior. Natural light is manipulated via a series of roof lights positioned to make best use of sunlight throughout the day and can also be used to passively ventilate and cool the space during the summer months reducing the mechanical load of the building. Seemingly frameless large windows and doors have been positioned to take advantage of beautiful views across adjacent meadows. Mention the external deck? The east / west axis is emphasised by framing the main window with a pair of 5m high opal glass screens that locate and provide privacy to a spa pool & cold plunge pool respectively.
Changing rooms have roof lights with 3.5m tall light funnels ensuring that all parts of this complex have natural light and ventilation. Floors throughout are finished with a textured porcelain tile The sauna and steam rooms are finished in a charcoal grey version of the tadelakt plaster. Only the steam room is finished in tadelakt, the sauna is in timber.
Although it is the energy hungry element on site, we have ensured that the fabric of the Pool House is super insulated with up to 400mm of insulation in the roof and 320mm in the walls. It is also super air tight achieving a minuscule air permeability of 3m3 per m2 at 50 PA external pressure (to put this into context the current Local Authority Building Control requirement for a new build house is 10m3 per m2) . These features ensure that the carbon neutral energy generated by the onsite Energy Centre is not wasted. The north side of the pitched roof is finished in a mat of sedum plants with the south side completed with a large 8.61kW array of photovoltaic solar panels generating electricity for the building as well as a 8no solar thermal panels. All pool equipment was carefully specified to be as energy efficient as possible.